Photochromic dyes are compounds that can reversibly change color, under the influence of environmental factors, such as for example light (e.g., ultraviolet light). Photochromic dyes are found in a variety of articles, most often lenses for glasses (e.g., photochromic lenses), automotive industry, sunroofs, etc. General classes of photochromic dyes include azobenzenes, salicylidene anilines, fulgides, spiropyrans, and spirooxazines. Very few photochromic dyes change color almost instantaneously when irradiated with light and also when an irradiation source is removed, while retaining the ability to repeatedly change color upon irradiation/removal of irradiation. Thus, there is an ongoing need to develop photochromic dyes.